The present invention relates generally to the treatment of arterial disease, including for example, aortic occlusive disease, and in particular, to an improved stent and method for treating arterial disease at or around the intersection of a plurality of arteries or blood flow passageways such as the intersection of the aorta and renal arteries or the aorta and posterior spinal arteries.
The prior art describes the treatment of arterial disease by various surgical techniques, some involving the use of stents and grafts. For example, it is well known in the art to interpose within the diseased portion of an artery a stent, whether made of stainless steel, nitinol or other materials, capable of being balloon-expandable for strengthening the walls of a stenotic or occluded artery. Similarly, it is also well known in the prior art to use a graft in conjunction with a stent to repair highly damaged portions of the aorta or other arteries thereby ensuring blood flow and reducing the risk of an aneurysm or rupture. Grafts, comprised of hollow tubes of material such as dacron, are normally inserted within the walls of a damaged artery and can be sewn into position or expanded through the use of a stented balloon catheter.
A more severe problem occurs when it is desirable to use a graft or a stent at or around the intersection of a major artery (e.g., the aorta) with intersecting arteries (e.g., the renal arteries). While the graft and stent is clearly preferred to strengthen and ensure the flow of blood through the aorta, the use of a stented graft effectively seals or blocks off the blood flow to collateral organs such as the kidneys. Accordingly, as described in U.S. Pat. No. 5,617,878 (Stent and Method for Treatment of Aortic Occlusive Disease), surgeons have devised various other techniques to repair weakened arterial walls in such cases including the use of a "bifurcated" stent comprised of a single stent and graft adapted through cutting to incorporate a second stent and graft. The technique, while effective, has proven cumbersome and somewhat difficult to employ and execute.
The present invention solves the problem of the prior art by providing a novel and improved device and method for treating arterial disease through the use of stented grafts at or around the intersection point of an occluded or diseased artery and another artery.